UWB Subharmonic Quadrature-IF Mixer and Image Rejection Mixer

• Main Authors: Chih-Hao Yang, 楊智皓
• Other Authors: Chi-Yang Chang
• Format: Others
• Language: en_US
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/20782607708265325630

碩士 === 國立交通大學 === 電信工程系所 === 96 === The UWB system is receiving growing attention as an important communication system for wireless communication. The characteristics of UWB system are the ultra wide bandwidth and its high data rate transmission. In order to obtain a better performance of the UWB system, an UWB mixer with the function of rejecting image signal is needed. An ultra broadband directional coupler is the most important element of the UWB mixer due to the large bandwidth. In first part of this thesis, we will utilize multisection structure to perform an UWB coupler. The most tightly coupling section of the multisection coupler is fabricated by VIP structure. The compensated stub, which can improve return loss and isolation of this coupler, is presented in this thesis. In the second part of this thesis, two kinds of mixers are discussed. The first one is a subharmonic quadrature-IF mixer, the phase difference between two output ports is 90 degree. The second one is a subharmonic image rejection mixer. All the mixers mentioned above have the benefits of small layout area and fewer elements.